Step-by-step explanation:
It is given that,
Time taken by a planet to orbit a star,
![T=4.34* 10^7\ s](https://img.qammunity.org/2020/formulas/physics/college/ii35kbv4rf8brlrw7sfz9j7sytflhlr4fm.png)
Radius of circular orbit,
![r=1.42* 10^(11)\ m](https://img.qammunity.org/2020/formulas/physics/college/s2dgplp2qkmpa77pwo422cbgdwacalc5f6.png)
(a) Angular speed,
![\omega=(2\pi)/(T)](https://img.qammunity.org/2020/formulas/physics/high-school/jdv8dwcawmf04t5e2701pgtk9w9oqvyi6f.png)
![\omega=1.44* 10^(-7)\ rad/s](https://img.qammunity.org/2020/formulas/physics/college/8ct20ax8r8jas19pzyie8mk7nln0grqjn6.png)
(b) Tangential speed of the planet,
![v=r* \omega](https://img.qammunity.org/2020/formulas/physics/college/8fc92hhcnyxz2py9suat48vwgqb8cpazcs.png)
![v=1.42* 10^(11)\ m* 1.44* 10^(-7)\ rad/s](https://img.qammunity.org/2020/formulas/physics/college/uoi7lll8fn9qchgczz30jlfz9sytcotqnw.png)
v = 20448 m/s
(c) Centripetal acceleration of the planet,
![a=(v^2)/(r\\)](https://img.qammunity.org/2020/formulas/physics/college/rrzrri9hxnv63jqom0zl7edwd51x5t90j1.png)
![a=((20448)^2)/(1.42* 10^(11))](https://img.qammunity.org/2020/formulas/physics/college/tvte7b3c10u196u54g1ystvyc9b8wzmpdv.png)
![a=0.0029\ m/s^2](https://img.qammunity.org/2020/formulas/physics/college/k4t105nih9b994f1dscolwiyfyhyp32yl3.png)
Hence, this is the required solution.